MDEV-14685 Assertion `!fully || (bool) hist_part' failed in Vers_part_info::initialized

sql/partition_info.cc

@@ -33,6 +33,7 @@
 #include "sql_acl.h"                          // *_ACL
 #include "sql_base.h"                         // fill_record
 #include "sql_statistics.h"                   // vers_stat_end
+#include "vers_utils.h"
 
 #ifdef WITH_PARTITION_STORAGE_ENGINE
 #include "ha_partition.h"
@@ -1168,6 +1169,17 @@ bool partition_info::vers_setup_stats(THD * thd, bool is_create_table_ind)
 
   bool error= false;
 
+  TABLE_LIST tl;
+  tl.init_one_table(
+    LEX_STRING_WITH_LEN(table->s->db),
+    LEX_STRING_WITH_LEN(table->s->table_name),
+    table->s->table_name.str,
+    TL_WRITE);
+
+  MDL_auto_lock mdl_lock(thd, tl);
+  if (mdl_lock.acquire_error())
+    return true;
+
   mysql_mutex_lock(&table->s->LOCK_rotation);
   if (table->s->busy_rotation)
   {

sql/vers_utils.h

@@ -16,8 +16,21 @@ class MDL_auto_lock
     thd(_thd), table(_table)
   {
     DBUG_ASSERT(thd);
+    MDL_request protection_request;
+    if (thd->global_read_lock.can_acquire_protection())
+    {
+      error= true;
+      return;
+    }
+    protection_request.init(MDL_key::GLOBAL, "", "", MDL_INTENTION_EXCLUSIVE,
+                            MDL_EXPLICIT);
+    error= thd->mdl_context.acquire_lock(&protection_request, thd->variables.lock_wait_timeout);
+    if (error)
+      return;
+
     table.mdl_request.init(MDL_key::TABLE, table.db, table.table_name, MDL_EXCLUSIVE, MDL_EXPLICIT);
     error= thd->mdl_context.acquire_lock(&table.mdl_request, thd->variables.lock_wait_timeout);
+    thd->mdl_context.release_lock(protection_request.ticket);
   }
   ~MDL_auto_lock()
   {